1. Field of Invention
This invention relates to a lighting device used primarily as a warning device or road flare. The device is normally stored in the trunk of an emergency vehicle until it is needed to alert oncoming drivers of a hazard in the road. It is commonly used by first responders such as policeman or fireman however it can be used by private citizens as well. In an emergency the user removes the light from his vehicle and places it in the road to signal to approaching vehicles the fact that a hazard exists. It is common practice for several of these devices to be placed in the roadway forming a wedge to guide approaching vehicles around the hazard. Currently both incendiary and electric road flares are in use.
It is important for the road flare to be compact and tough. It must be easy to transport and capable of withstanding vehicle run over. It is also important for a road flare to be highly visible as it is common for a small quantity of road flares to have the task of effectively alerting oncoming drivers of a hazard.
Finally it is important for these road flares to withstand vehicle run over without damage and without shifting from their deployed location. Its ability to both alert and guide drivers depends upon a number of factors including its intensity and the perceived size of its illuminating surface.
2. Prior Art
Prior art identification of short term road hazards includes small electric lights, electric road flares or incendiary road flares that are normally placed directly on the road. Prior art electric road flares are also usually designed to be run over by oncoming vehicles without sustaining damage. Road flares are normally placed directly on the roadway as this deployment does not require bulky supporting cones or brackets. However, some suppliers design their road flares to additionally be deployed on brackets or rubber cones as this lifts the road flare closer to eye level so that it can be more easily seen by oncoming drivers.
Led light sources which are the light sources employed in most of the electric road flares typically emit their light into a hemisphere. If the road flare is to be deployed primarily directly on the road with its base horizontally disposed the design objective would normally require a more intense light along the horizontal direction. This would be accomplished with a light concentrating lens. Some led lamps are available with integral light concentrating lenses which concentrate the light about the center of the hemispherical emission pattern of the led emitter. These led lamps are in use in prior art designs as shown in FIG. 13 to be later described. These prior art designs comprise a circle of led lamps (typified by a commercial T 1¾ led lamp) disposed in a horizontal plane and directed radially outward with each led lamp having its own lens for concentrating its individual emitted light into a horizontal beam. The light from the circle of led lamps combines to form a horizontal light beam. These designs create a road flare having a concentrated horizontal light beam and a compact pancake contour without projections.
Other prior art suppliers which deploy their road flares on the roadway and in a plurality of other orientations relative to the observer simply place the led light source directed vertically upward in a housing without a horizontally concentrating lens. In these designs the emitted light substantially fills the hemisphere above the road flare. In these designs only a small fraction of the light is emitted along the horizontal direction. These prior art road flares when placed directly on a roadway do not concentrate a large percentage of their emitted light along the horizontal however they do provide a road flare which is visible from most angles of approach within the upper hemisphere. This design is visible as a device placed on the roadway, attached to a bracket and rotated or when viewed from helicopters. However, since its emitted light is not concentrated about the horizontal during roadway deployment it is substantially less intense when on the roadway and viewed by oncoming drivers. FIGS. 10 through 12 to be later described represent these prior art designs.
Prior art does not include the following features:                Prior art does not provide an electric road flare for disposition on a roadway with a a single led light source emitting light that is collected by a lens into a substantially horizontal light beam.        Prior art does not provide an electric road flare for disposition on a roadway having an led emitter emitting light that is collected by a lens into a substantially horizontal beam and further comprising a reflective surface exterior to the lens redirecting a portion of the horizontal beam emerging from the lens diverging from the horizontal towards the horizontal.        Prior art does not provide an electric road flare for disposition on a roadway with a single led light source emitting light that is concentrated into a horizontal light beam visible throughout the azimuth.        Prior art does not provide a compact electric road flare for disposition on a roadway and emitting a horizontal light beam from a location above its housing and at a maximum height above the roadway        Prior are does not provide an electric road flare which collects the heat created by its light creating element into a small exterior light transmitting surface to encourage melting of snow on the surface.        Prior art does not provide an electric road flare that is low in profile having a contour that is structurally strong enough to withstand vehicle run over and that resists flipping over or location shifting during vehicle run over.        